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The BEST is yet to come - Richard Muller on the Berkeley Earth Surface Temperature Project, whether he's a 'skeptic', and BEST’s climate policy ambitions

03 Aug 2012, 11:20

Ros Donald

We talk to Berkeley Earth Surface Temperature (BEST) project
co-founder Richard Muller about plans to branch out into climate
policy studies, and why he's confident BEST will encourage
consensus between skeptics and mainstream climate scientists in the
end.

This week BEST released the latest
in a series of papers, confirming the project's announcement last
year that the Earth has warmed at the rate that previous studies
suggested. This time BEST went further, also concluding that
warming is most likely due to manmade greenhouse gas
emissions.

BEST the media phenomenon

Professor Muller's phone hasn't stopped ringing since his
op-ed in the New York Times over the weekend, where he stated
that BEST's new research has answered his own doubts about whether
humans are causing global warming. His self-described conversion to
the mainstream scientific view linking human activity to climate
change has captured the imagination of a media often wary of
reporting on climate change.

Yet the story in the press - describing a 'skeptic's' Damascene
conversion - doesn't seem to make sense. In fact, in his 2009 book
Physics for Future Presidents, Muller doesn't question the
fundamentals of climate science, or indeed that humans are
contributing to the greenhouse effect.

Asked if it's really accurate to say he was ever a skeptic, Muller
replies: "I have considered myself only to be a properly skeptical
scientist. Some people have called me a denier - no, that's
completely wrong. If anything, I was agnostic.

"I just hope that some people like you will read my books and
papers, and read what I say - not what people say I say."

That's not to say he still doesn't have problems with sweeping
statements about climate change: "90 per cent of what's said about
climate change is nonsense. That when people attribute Hurricane
Katrina, or dying polar bears, that's not based on any science
whatsoever. In fact in many cases, it's wrong. So there's plenty of
room for skepticism.

"What we have addressed is the critical issue of temperature
change, and we've come up with answers that I think illustrate what
happens when science is done in a straightforward and transparent
way."

What about the results?

Some scientists have
wryly noted that in confirming the conclusions of other groups
that examine global temperatures, BEST has essentially spent two
years getting to where climate science was in the 1990s. Asked why
he wanted to retrace other groups' steps, Muller says he felt
"major issues were raised about previous studies", to such an
extent that he feared they didn't reach "scientifically solid
conclusions".

What did it take for Muller to address the concerns he says he
first felt three years ago when emails between scientists at the
University of East Anglia's Hadley Centre - the keeper of one of
the world's three major surface temperature datasets - were
leaked?

The team collected all of the temperature data it could from
around the world because, he says, other studies had "only used a
fraction" of what was available.

Next, the team set about addressing concerns raised by skeptics
and others about existing Earth surface temperature datasets and
their findings. Muller elaborates "First, there were issues around
[weather] station quality - [skeptic meteorologist and blogger
Anthony] Watts showed that some of the stations had poor quality.
We studied that in great detail. Fortunately, we discovered that
station quality does not affect the results. Even poor stations
reflect temperature changes accurately."

"There were issues of data changes. Some of the prior groups had
adjusted the data and lost all record of how they had adjusted it.
So we went back to the raw data and used only that."

"Then, there's the urban heat island effect [the criticism that
weather stations sited in urban areas give artificially high
temperature readings]. That was something I think we studied in a
clever and original way," Muller says. This involved examining only
the data from rural stations to see if the temperature rise was
still there - and it was. "We got the same answer," he says.

Finally, there were the models. Muller says: "The existing
conclusions were based on extremely complex global climate models.
With these, you could never track down how many adjustable
parameters they had, or how many hidden assumptions there were. We
used a very simple approach."

But discovering his findings agreed with the scientists at the
heart of the so-called Climategate leak hasn't led Muller to soften
his view of what he calls the "scientific misconduct" uncovered. He
says: "As scientists, we have to be completely open with our data.
The UK group purposefully hid the discordant data, and they did it
in order to make sure that people drew the same conclusions that
they drew. To me, that's misconduct."

Answering the critics

Criticism of the BEST project has come thick and fast, uniting
skeptics and mainstream voices in condemning both the group's
methods and its decision to release its findings before they
underwent peer review.

The BEST method, devised by physicist Robert Rohde - who Muller
says did "most of the work" on the project - has been
criticised for being too simplistic. But Muller argues that the
approach "leads to the smallest uncertainties in determining the
record. And that was absolutely key for us to reach our
conclusions." He adds" "There's been a lot of knee-jerk reaction to
this because we've done something in what I consider a more elegant
way."

"I think many people - many of whom I notice have never discovered
anything in their life - believe that in complexity lies the truth.
But the glory of physics is that things sometimes hit you in the
face. And that's the case here."

One of the strongest voices criticising the study comes from the
BEST team itself. Dr Judith Curry, head of the School of Earth and
Atmospheric Sciences at the Georgia Institute of Technology,
declined to be a co-author on the latest BEST study, and says on
her blog she does not "see any justification in [BEST's] argument
for" the group's statement that its warming data fits with manmade
carbon dioxide. Curry's not alone: former climate scientist William
Connolley
claims BEST has done "none of the attribution work you'd
expect".

Muller says Curry distanced herself from the paper because she
disagrees with the findings, and that she has an alternative theory
- that the climate is random, so any correlation between increases
in carbon dioxide and warming is an accident. His response: "'I've
said to her that the unfortunate aspect of her theory is that it's
untestable. Now a theory that's untestable is not something I
consider to be a theory."

Then there's skeptic blogger Anthony Watts. Rolling back his
previous promise to accept BEST's findings, the one-time BEST
supporter has released a draft paper of his own, at about the same
time as the new BEST results. Watts says his assessment of
temperature stations shows that poor weather station siting has
"spuriously" doubled estimates of temperature rise in the US, and
that "[the] issue of station siting quality is expected to be an
issue with respect to the monitoring of land surface temperature
... in the BEST network."

But Muller dismisses the suggestion that Watts released his work
to counter the new BEST study. "[Watts] didn't even know about our
work," he says. "Our work on station quality agreed with [previous
work Watts] published," he adds. "Now he's saying: 'If I use a
different criterion I find that the uncorrected data can yield a
bias'. Well, that sounds reasonable - if a station moves and you
don't take that into account, yeah, you're likely to get a bias. I
don't see any really strong objection to that. What he has done was
interesting, but it doesn't affect our new conclusions."

Meanwhile, economics professor and climate skeptic Ross McKitrick,
who was one of the BEST referees, called for major reviews to be
made to last year's papers - especially in relation to station
siting and urban warming.

Again, Muller is sanguine: "There were no mistakes in that paper.
McKitrick had comments and found things he thought were mistakes,
but we wrote back to him and told him he was wrong." He adds: "I
think the conclusion that urban heat islands contribute essentially
zero to the warming we see is on very solid ground." Indeed, due to
BEST and studies that went before it, Muller says that the question
of whether urban heating skews warming data is no longer a
legitimate quibble with data that shows warming.

Could BEST really "cool the debate"?

Such a volume of criticism from sceptics and the mainstream alike
may not be what Muller had in mind when he said in 2011 that he
hoped the BEST project would help "
cool the debate" between the two sides.

But Muller believes BEST will win through in the end. "I don't
think anybody who has responded in the media so far has actually
studied our work. We don't expect immediate agreement on such
things," he says.

He adds: "What we expect is that by being transparent, open and
clear. By having the data online and the computer programmes so
people can see precisely what we did, that - over the coming weeks
and maybe months - that gradually the debate will be cooled and
people will recognise what it is we really did. And that we will
forge a scientific consensus - that we will help with that."

Muller says: "I think that many of the skeptics are, indeed,
open-minded. But until they really look at what we did they
properly should remain skeptics, and not be convinced by an op-ed
piece."

BEST beyond the hype

Although he's clearly not banking on change coming overnight,
Muller might still be accused of over-confidence in the scope for
agreement in the polarised climate debate. But he's not waiting
around. In the meantime, he has big plans - to develop BEST's remit
to include measurements of ocean temperature and a study of ocean
currents. One BEST paper on ocean currents has already been
accepted and is awaiting publication, he says.

Meanwhile Elizabeth Muller, Professor Muller's daughter and the
co-founder of the BEST project, is interested in "starting a new
section to look at policy," Professor Muller says, to examine "in
an objective scientific manner what can be done".

In a follow-up email, Elizabeth Muller, who is a former OECD
policy advisor, fleshes out the plans. She says the idea is to
focus on policy that could have an impact on future greenhouse gas
emissions. These policies, she says, must be "low cost,
cost-neutral or, ideally, profitable." Two examples she lays out in
an op-ed article in the San Francisco Chronicle are clean fracking
- making extracting unconventional natural gas greener - and energy
efficiency.

This new direction - no matter how transparent the work - raises
the possibility of a conflict between scientific objectivity and
advocacy. Muller concludes our interview saying: "I think that
science is that small realm of knowledge in which universal
agreement can be achieved. Let's do that with climate science, and
then lets leave to the politics and the diplomacy what can be done
about it." Yet with this new plan, BEST looks set to join the
politicians in the fray - a move that's unlikely to quieten the
critics. Instead of cooling the debate, it's likely to raise new
questions about science's place in society. But whether you like
that or not, it appears BEST is here to stay.